The numerous varieties may, for practical purposes, be grouped in two
classes--Cabbage and Cos Lettuces. They vary greatly in habit and are
adapted for different purposes, the first group being invaluable for
mixed salads at all seasons, but more especially in winter and early
spring; the second group is most serviceable in the summer season, and
is adapted for a simple kind of salad, the leaves being more crisp and
juicy. A certain number of the two classes should be grown in every
garden, both for their great value to appetite and health, and their
elegance on the table, whether plain or dressed. In the selection of
sorts, leading types should be kept in view. Some of the varieties which
have been introduced have no claim to a place in a good list, because of
their coarseness. Although they afford a great bulk of blanched
material, it is too often destitute of flavour, or altogether
objectionable. The best types are tender and delicately flavoured,
representing centuries of cultivation, and the sub varieties of these
types should retain their leading characteristics, though perhaps they
are more hardy and stand longer, and are therefore much to be desired.

==Preparation of the Soil==.--The Lettuce requires a light, rich soil, but
almost any kind of soil may be so prepared as to insure a fair supply,
and in places where fine Cos Lettuces are not readily obtained, it may
be possible to grow excellent Cabbage varieties in place of them. A
tolerably good garden soil will answer for both classes, and fat stable
manure should be liberally used. The best way to prepare ground for the
summer crop is to select a piece that has been trenched, and go over it
again, laying in a good body of rough green manure, one spade deep, so
that the plant will be put on unmanured ground, but will reach the
manure at the very period when it is needed, by which time contact with
the earth will have rendered it sweet and mellow. By this mode of
procedure the finest growth is secured, and the plants stand well
without bolting, as they, are saved from the distress consequent on
continued dry weather. As regards drought, it must be said that the
red-leaved kinds stand remarkably well in a hot summer, and although
they do not rank high as table Lettuces in this country, were we to
experience a succession of roasting summers they would rise in repute
and be in great demand. Cabbage Lettuces bear drought fairly well, more
especially the diminutive s